Camptosaurus prestwichii, Hulke, 1880

Mcdonald, Andrew T., 2011, The taxonomy of species assigned to Camptosaurus (Dinosauria: Ornithopoda), Zootaxa 2783, pp. 52-68 : 60-61

Cumnoria prestwichii Hulke, 1880

1880 Iguanodon prestwichii Hulke , p. 454.

1888 Cumnoria prestwichi (sic) Seeley, p. 698. 1889 Camptosaurus prestwichi (sic) Lydekker, p. 48.

1909 Camptosaurus prestwichii Gilmore , p. 285.

1980 Camptosaurus prestwichii Galton & Powell , p. 412.

Holotype. OXFUM J.3303, partial skull and postcranium.

Locality and horizon. Chawley Brick Pit, near Cumnor, Oxfordshire, UK ( Galton & Powell 1980); Kimmeridge Clay Formation, Kimmeridgian.

Generic diagnosis. As for the species by monotypy.

Specific diagnosis. Basal styracosternan distinguished from all other iguanodontians except Uteodon aphanoecetes by a unique combination of characters; the same unique combination of characters distinguishes Uteodon aphanoecetes (see ‘Specific diagnosis’ above). Distinguished from Uteodon aphanoecetes by an occipital condyle that does not project farther ventrally than the basal tubera ( Figs. 7 B, C).

Remarks. Cumnoria prestwichii was originally named as a new species of Iguanodon ( Hulke 1880) , as were numerous different basal iguanodonts in the 19th Century. Seeley (1888) subsequently erected the new genus Cumnoria for “ I.” prestwichii . This designation was almost immediately challenged by Lydekker (1889), who referred the species to Camptosaurus . Later authors have largely followed Lydekker’s decision (e.g., Gilmore 1909; Galton & Powell 1980; Norman 2004), although in a recent historical overview of British dinosaurs, Naish & Martill (2008) suggested that using Cumnoria might be preferable in light of new information on the skull of Camptosaurus ( Brill & Carpenter 2007) .

The phylogenetic analysis supports Naish & Martill’s tentative proposal, recovering “ Camptosaurus ” prestwichii in a polytomy at the base of Styracosterna with Uteodon aphanoecetes in the reduced consensus tree. Thus, the generic name Cumnoria is reinstated for the species Cu. prestwichii . Cumnoria prestwichii was coded based upon the holotype and only known specimen, OXFUM J.3303. See ‘Remarks’ on Uteodon for further discussion of the relationships of Cumnoria.

Figures

FIGURE 7. Partial braincases of Camptosaurus dispar, Uteodon aphanoecetes, and Cumnoria prestwichii. (A) YPM 1880 in left lateral view (image copyright YPM); (B) CM 15780 in right lateral view (image courtesy of M. Lamanna); (C) OXFUM J. 3303 in right lateral view. Abbreviations: bt, basal tubera; oc, occipital condyle. Scale bar equals 5 cm.